George Pantalos, a University of Louisville professor of surgery and bioengineering, tests a prototype of surgical device designed to aid surgery in zero-gravity during long space missions. / Gannett

by By Chris Kenning, The (Louisville, Ky.) Courier-Journal

by By Chris Kenning, The (Louisville, Ky.) Courier-Journal

LOUISVILLE, Ky. -- What happens when astronauts are hurtling toward Mars on a years-long space voyage and one is injured, requiring emergency surgery in a environment lacking gravity?

It may sound like science fiction, but it's one of the challenges NASA faces in its goal of putting astronauts on Mars by 2035. And it has spurred a University of Louisville researcher to test a potentially lifesaving surgical device aimed at helping make zero-gravity surgery possible.

George Pantalos, a professor of surgery and bioengineering, and colleagues from Carnegie Mellon University are conducting four days of tests this week in Houston aboard a NASA zero-gravity jet known as the "vomit comet," which flies in gut-churning parabolic arcs to generate 20 to 30 seconds of weightlessness.

They're testing prototypes of an "aqueous immersion surgical system" -- an airtight and watertight dome with surgical ports that would be filled with saline and surround a wound in a zero-gravity environment. The idea is to stop bleeding and contain fluids that would otherwise float through the spacecraft, potentially endangering the patient and crew.

To test the concept, the researchers used plastic containers inside a prenatal care box. The researchers, held in place by foot straps, successfully controlled artificial blood coursing through a simulated vein Tuesday. On Wednesday, they conducted a simulated surgical procedure on a pig's heart.

"We're grateful that it turned out so well," Pantalos said by phone Tuesday night from Ellington Field at the Johnson Space Center Reduced Gravity Program, adding that he hopes the device eventually could be used in other challenging environments, such as war zones.

Pantalos, 60, is working on the device with Pittsburgh-based Carnegie Mellon bioengineering researchers James Antaki, Jennifer Hayden and James Burgess.

Although the United States has retired its space shuttle program, President Obama in 2010 announced that his goal is to have a manned flight reach an asteroid by 2025 and Mars by the mid-2030s, a round-trip mission likely to take several years.

Interest in Mars has grown recently with NASA's successful landing of the Curiosity rover, which landed on the red planet in August after an eight-month journey.

Pantalos is one of many researchers working on the challenges of extended space travel. Those include health care concerns, such as the rapid loss of bone density, wounds that heal slowly in space and the possibility of having to do medical procedures using remote-controlled robots.

"NASA is looking at all the stuff they need to develop over the next 10 to 15 years to get ready for long-duration missions," Hayden said.

Her team's device has no NASA funding, but the agency is helping by allowing them to use the zero-gravity aircraft. And they hope to use their results from this week to get a NASA grant to study it further.

Pantalos, attached to the University of Louisville's Cardiovascular Innovation Institute, is a veteran of space flight research. He's conducted tests on 28 weightless flights, in one instance developing a modified zero-gravity heart resuscitation procedure that is now part of astronaut training.

When Antaki contacted him about the idea for space surgery, originally conceived of by Burgess, Pantalos was intrigued.

"Let's say you're on your way to Mars. That takes nine or 10 months. Part-way there, one crew has an acute case of appendicitis. On Earth you'd think nothing of it, go to the ER and you're discharged next day," he said. "In space it's not quite so easy."

Hayden said rare medical emergencies on the International Space Station orbiting the Earth are currently handled by evacuating patients -- which has happened twice with Russian cosmonauts, including one with a heart problem.

There has been previous research on surgery in zero gravity.

In the early 1990s, researchers on the NASA plane conducted surgery on a rabbit in a clear box. In 2006, French doctors conducted the first operation on a human in a zero-gravity plane, removing a cyst from a man's arm.

NASA has also conducted robotic surgery experiments in an undersea lab off the coast of Florida.

Hayden said the device and surgery could be used in cases where astronauts have limbs crushed in accidents or have unforeseen medical problems.

"In the weightless atmosphere of deep space, the absence of gravity will make it nearly impossible to control the escape of blood and bodily fluids during surgery," Pantalos said. "This lack of control would both compromise the health of the patient as well as contaminate the spacecraft cabin."

To avoid having blood form into spheres in zero gravity and float toward the walls of the spacecraft, the team developed the idea for a structure resembling a transparent dome the size of half a grapefruit. But it could also take other forms, depending on the part of the body undergoing surgery.

Water or saline can be pumped through the device to safely remove blood and other body fluids, or to control bleeding. Reducing blood loss would be important with a limited supply.

Pantalos said they tried the test without liquid in the chamber, and blood covered the walls of the device, making it impossible to see. But with the liquid, they were able to create suction and control bleeding during 25 parabolic flight arcs on the first day.

A pig's heart was put in another version, this one a modified plastic cookie jar that Hayden purchased at Bed, Bath and Beyond.

"We have more tests and development, but I think using an aqueous system may be a reasonable approach," Pantalos said.